The US's Open Door Policy in the Middle East

After World War One, the Middle East was a battleground of economic competition between oil companies. The British exercising their colonial power were first to establish control over Middle Eastern oil. But then the US insisted on a share of its own. What did the ultimate settlement look like once the colonial powers and their national oil majors had divided up all the region's oil concessions amongst themselves? And how how did that both make and reflect the colonial order in the Middle East?